The Government is facing a crucial week over the prospect of the biggest strike since the coalition came to office, amid growing anger over pay restraint in the public sector.
The country's biggest trade unions are balloting hundreds of thousands of council workers in England and Wales in protest at an offer worth 1% for most staff.
Unison will announce the result of its ballot today, followed by the GMB and Unite over the next week.
The Public and Commercial Services union is also balloting its members for a strike in a long-running dispute over cuts in the civil service, with the result also due by the end of the month.
If workers vote yes, there will be a one day strike on July 10, which Unison general secretary Dave Prentis has predicted could be bigger than the General Strike.
Members of the National Union of Teachers will also take industrial action on July 10, while firefighters in England and Wales have staged a series of walkouts over pensions over the past year and have not ruled out further stoppages.
Meanwhile, midwives in England could soon be balloted for industrial action in protest at the Government's controversial decision not to accept a recommended 1% across the board pay rise for NHS staff.
Thousands of midwives and maternity support staff are currently being consulted on whether they want a formal ballot for action.
Jon Skewes, director of policy and employment relations at the Royal College of Midwives, said: "Midwives are really angry that the Government said to them they'd get a 1% pay rise but now only staff at the top of their pay scales will get that rise, and it's not consolidated into their pay.
"Jeremy Hunt (health secretary) has picked out health workers for harsher treatment on pay than anyone else in the public sector.
"This is the time for midwives to take a stand because the Government is intent on assaulting their pay and conditions."
Other health unions are warning of ballots for industrial action, which could see a second wave of public sector strikes in in the autumn.
At the opening of the annual conference of the Rail, Maritime and Transport union in Bristol, acting general secretary Mick Cash reinforced calls for co-ordinated action against cuts and the threat to jobs and working conditions.
He said: "This is the first RMT AGM since the death of our general secretary Bob Crow but the fighting, militant organisation that was built under Bob's leadership remains in place as we have shown in a wave of recent disputes from London Underground to Heathrow Express and in on-going campaigns to defend our members' jobs, pay and working conditions.
"RMT has long argued for a policy of co-ordinated and generalised strike action that unites every group of workers threatened with the cosh of austerity and it is encouraging to see that that position is gaining traction the length and breadth of the trade union movement.
"Our AGM here in Bristol will lay out the framework for our campaigns and action for the year ahead - fighting against the rail franchising shambles that threatens jobs and safety in the name of greed and profit, demanding investment in modernisation and capacity and continuing the battle against zero hours contracts and casualisation."